Read section 8.11 and use the figures to answer questions 20-21.

Figure 8.20


Scientists have melted holes in the bottom of the world, near the South Pole. Instruments lowered into these holes are now being used as astronomical observatories. The first version of this observatory was known as the Antarctic Muon and Neutrino Detector Array (AMANDA). The newer and bigger version of this observatory is now known as Ice-Cube, spanning a cubic kilometer of ice! Astronomers lower into each melted hole a string knotted with basketball-sized light detectors. The water in each hole soon refreezes. The detectors are sensitive to blue light emitted in the surrounding clear ice. Such light is expected from ice collisions with high-energy neutrinos emitted by objects or explosions out in the universe. Analyses of data from the AMANDA II and Ice-Cube detectors have been used to create the first maps of the high-energy neutrino sky. (Click on the above images for larger, more legible, versions). UA astronomers are now working on this exciting, second-generation version of this observatory, known as Ice-Cube. Ask your lab instructor for more information!


Figure 8.21

The first map of the high-energy neutrino sky, produced with data from the AMANDA II and newer Ice-Cube observatories at the South Pole provide tantalizing glimpses of many potential point sources of ghostlike cosmic neutrinos. This AMANDA map was released on July 15, 2003, and the Ice-Cube map in December of 2010. WARNING: This map is not in galactic coordinates, but in Right Ascension and Declination. The red line corresponds to the celestial equator.

map of the high-energy neutrino sky
Used with permission by: UW-Madison University Communications 608/262-0067. Photo courtesy of AMANDA Project. July 2003.


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